On the back of the white plastic cover there is a hole with 8 marks around it. Put a small flat head screwdriver into it. Turning it counterclockwise will speed the clock up. Every 8th of a turn it gains or loses about 5 minutes a day.

Record what time another clock says and set your clock to that exact time. Turn the screw an 8th turn counterclockwise and let the clock run. The next day when the first clock says what it said the day before, check your clock to see if it says the same thing. If not keep adjusting the screw. It'll take a long time but your clock will tell the exact time.

On the back of the white plastic cover there is a hole with 8 marks around it. Put a small flat head screwdriver into it. Turning it counterclockwise will speed the clock up. Every 8th of a turn it gains or loses about 5 minutes a day.

Record what time another clock says and set your clock to that exact time. Turn the screw an 8th turn counterclockwise and let the clock run. The next day when the first clock says what it said the day before, check your clock to see if it says the same thing. If not keep adjusting the screw. It'll take a long time but your clock will tell the exact time.